Measured electrical constants of 270-mile 154-kv transmission line

C. F. Wagner (Westinghouse Electric and Manufacturing Company, East Pittsburgh, Pa.): The principal value of this paper lies in the comparison between measured and calculated values of the constants of transmission lines. Naturally, therefore, the authors should be explicit in defining the assumptions made in the calculations. Frequently in calculating the characteristics of transmission lines the separation of conductors is taken as the values at the tangent towers. The authors in this instance have gone beyond this assumption and have averaged the separation, taking into consideration the difference in sag of the ground wires and conductors. Further clarification of the method of averaging is desirable. A statement from the authors is also desirable regarding the assumption used in determining the length of conductors. Did they use merely the geographical length of the line, or did they compute the constants on the basis of the actual length of the conductors, taking the sag into consideration? Further clarification is also desirable regarding the basis for using an earth resistivity of 100 ohms per meter cube.